Alexandra finds that she can give 3 haircuts and 2 hair dyes in 315 minutes. Giving 2 haircuts and 4 hair dyes takes 450 minutes. How long does it take her to do a haircut?
3x + 2y = 315
2x + 4y = 450

Hassan bought a package of tofu. the temperature of the tofu was 14° celsius when hassan put the package into the freezer. he left the tofu in the freezer until it reached –19° celsius. which expressions explain how to find the change in temperature, in degrees celsius, of the package of tofu? select three that apply.